Lost AC Pwr..adapter works

My Dell Inspiron 9200 running XP no longer recognizes the AC adapter at all. It is the same whether plugged in or not...the battery indicates no AC pwr. I verified the adapter is working properly. Is there something simple I can change on the system board or do I need to replace the system board (I sincerely hope not!).
Thanks for any help on this...Hirshy

Edited by hamluis, 18 February 2011 - 11:26 AM.
Moved from XP forum to Internal Hardware.

If you have a voltmeter, or have access to one check to see if there is any output from the power adapter.

Also check the connection to see if it is loose. With laptop computers this is a common problem.

I you need instructions for the use of a voltmeter I can provide them.

Yes...before I posted, as I mentioned, I verified that the adapter was putting out the correct voltage.
I also went to the system board and re-soldered all the connections to the pwr input jack. This corrected the problem in the past. But obviously something else is not allowing pwr from the adapter to get through.

What's the next step? Thanks for your help!!

Solder in a new power jack to the motherboard. They do break internally.

Sometimes when a jack comes loose, it pulls/breaks the copper traces on the motherboard. Clean the solder points/holes on the mobo, make sure solder is actually sticking in the holes. A vac desolder tool (~$5-10) is nice to have to pull out the solder so you can see what is going on. I even have a tiny wire drill set that I use to clean them out as well.

Something to remember that on 4 layer boards, with few exceptions, the power and ground layers are the base layers, the signal planes are on the outer layers. Just because a solder joint looks good on the surface, doesn't mean it is contacting properly where it should.

Ok...sounds easy enough. I was hoping I wouldn't have to buy a new mother board.
I will try and find a power jack and solder it in.
I will be back to let everyone know what happens!

I just installed the new jack.
No go. Same issue. When you said it's a four layer board, does that mean I have to solder the leads on the top of the board as well as the bottom. I already provided enuf heat for the solder to run thru the board.

This is very frustrating!!!

Thanks!

Most manufacturers use a technique know as through hole soldering. The solder flows through the hole soldering both the component and trace sides of the board.

The important part of the solder joint is the trace side, there needs to be a good solder connection between the component leg and the trace. Don't over heat the traces, this can cause the trace to lift off the board.